Hello Philipp,

Thank you for purchasing Amelia, and for reaching out to us.

Issues like this can occur if your WordPress site is set to be in a different time zone. Since Amelia doesn't have any time zone settings, it inherits the time zone from WordPress. If your time zone is in UTC+/- format, please change it by selecting the city near you. Also, please check if you enabled "Show bookings in customer's time zone" in Amelia's General settings.

If you are in a different time zone than your WordPress site is, and you've enabled this option, the times on front-end will show available time slots in your time zone, which will be the time you set in back-end +/- the time difference (depending on where you are in regards to the time zone set in WordPress' General settings). 

You can read more about it in this Article: Time Zones with Amelia 

Also if you created your employees before you configured Global Working Hours, those employees picked up the Company’s working hours which come as default with the plugin (09:00 – 17:00).

Employees can have different working hours than those of the company, so to configure availability for your services, you need to configure the working hours of employees assigned to those services. 

Employees’ working hours override the company’s working hours. To set them up, you need to go to the “Employees” section, select the employee, and configure their schedule from the “Work Hours” tab, also please check if you have set up buffer time after.

If you have any more questions please feel to open another ticket.